Marines on Iwo Jima, side view of M-1941 Haversack, February 1945.
The USMC M-1941 Haversack (upper bag) and Knapsack (lower bag) were a two-piece pack system issued to Marines in World War II. The Haversack had two straps to hold down the main flap, and separate blanket roll straps were used for a horseshoe rollup around the pack. A flap with eyelets was provided on the top center for an Intrenching Tool and a hold-down strap on the pack front held the handle of the tool. The pack suspenders (Suspenders, Web Belt M-1941) had two straps that crossed over in back, but were not connected. They used snap hooks to attach to the belt. Shoulder straps could be used instead of the suspenders. A second eyelet flap on the right side was intended for a bayonet or any equipment with the M-1910 hooks.
The knapsack had two straps to close its main flap and side straps to hold the lower arms of the horseshoe blanket roll (if rolled the long way). Short straps on the bottom of the Haversack attached the knapsack, when it was used.
Marines on the beach, wearing M-1941 haversack with camouflage blanket roll, Guam, 1945.
All components of the M-1941 pack system were in USMC pre-war "mustard tan" or khaki for World War II, although OD #7 was used later and even nylon versions in early Vietnam. Typical markings included "USMC" inside the flap along with manufacturer "BOYT" and date indications, such as "44".
This pack was difficult to adjust to in actual use and was not popular with the Marines who had to carry it.
Early and Late Pattern USMC M1941 Packs
The early pattern M-1941 haversack and knapsack each had two "dog ear" side flaps that folded over the opening from each side. The top flap then folded over and was closed by two small straps and buckles. In the early pattern, the haversack had an integrated set of shoulder straps and did not depend on suspenders. This system was not waterproof.
The modified "second pattern" haversack and knapsack were introduced in 1943 with a simplified closure system. They have "roll flaps", an extension of the pack bag body that are folded over for a secure, somewhat waterproof closure. The folded extension is the top flap of the pack that attaches to the outside straps.
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